46 lines
747 B
Go
46 lines
747 B
Go
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package cache
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import (
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"io/ioutil"
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"path/filepath"
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"github.com/docker/docker/pkg/symlink"
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"github.com/moby/buildkit/snapshot"
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"golang.org/x/net/context"
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)
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func ReadFile(ctx context.Context, ref ImmutableRef, p string) ([]byte, error) {
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mount, err := ref.Mount(ctx, false)
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if err != nil {
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return nil, err
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}
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lm := snapshot.LocalMounter(mount)
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root, err := lm.Mount()
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if err != nil {
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return nil, err
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}
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defer func() {
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if lm != nil {
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lm.Unmount()
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}
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}()
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fp, err := symlink.FollowSymlinkInScope(filepath.Join(root, p), root)
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if err != nil {
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return nil, err
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}
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dt, err := ioutil.ReadFile(fp)
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if err != nil {
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return nil, err
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}
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if err := lm.Unmount(); err != nil {
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return nil, err
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}
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lm = nil
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return dt, err
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}
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